JP5160203B2 - Polyester heat shrinkable film roll - Google Patents

Description

  The present invention relates to a polyester-based heat-shrinkable film roll, and more specifically, a polyester-based heat-shrinkable material that is suitably used for shrinkage labels, food packaging, etc. without causing problems such as printing misalignment and solvent seal slippage during printing and bag making. It relates to a film roll.

Conventionally, stretched films made of polyvinyl chloride, polystyrene, or polyester have been mainly used as shrink labels used for glass bottles and polyethylene terephthalate bottles (pet bottles) and shrink films for food packaging.
These heat-shrinkable films are mainly formed into a master roll by the tenter stretching method, and then wound into a roll while slitting at an arbitrary width, and subjected to gravure printing mainly in the width direction in the form of a roll. It is done. Then, after slitting to the width | variety of each surface and winding up in roll shape, it is bag-formed by methods, such as solvent adhesion | attachment, in a tube shape, and is wound up in roll shape (label roll).
The bag-made product is then cut into the length of the coating, and then covered with the coating, and is thermally contracted by passing through a contracting tunnel that is blown and contracted by spraying steam or hot air, thereby closely contacting the coating.

  As a feature in recent years, with the increase in the number of products, the number of colors can be reduced without producing a large number of plates, and high-precision photo printing, which is advantageous in terms of cost, has increased. On the other hand, high-precision printing such as gravure printing and gradation printing exceeding six colors that require a high degree of design is also increasing.

  FIG. 5 is a diagram schematically showing a gravure printing process in shrink film printing. In FIG. 5, the film 100 unwound from the unwinding roll 51 shown on the left side of the drawing is shown in the center of the drawing, for example, a six-color gravure multicolor printing machine 520 (in the drawing, two of the six colors are 2 The portion for printing the color is shown, and the portions for printing the other four colors are omitted.) After that, the portion is wound on the winding roll 518 shown on the right side of the drawing. In the gravure printing machine 520, for example, red and blue inks are stored in the ink reservoirs 52a and 52b arranged in the lower part. The ink reservoirs 52a and 52b are provided with ink winding rolls 53a and 53b so as to be immersed in the respective inks. Plate rolls 53a and 53b engraved with printing patterns and characters are arranged on the surface, respectively, and impression cylinder rolls 55a and 55b are arranged above them so as to be in contact with these plate rolls. Three adjustment rolls 511, 512, 513; 514, 515, 516 are arranged on the upper part of the printing machine 520 corresponding to the respective ink reservoirs 52 a, 52 b. The film 100 unwound in the horizontal direction from the unwinding roll 51 reaches the adjustment roll 511 vertically upward via the direction changing roll 510. Thereafter, it passes through two adjustment rolls 512 and 513 and reaches the contact roll 55a. Here, the plate roll 53a, the lower part of which is immersed in the ink reservoir 52a storing the red ink, which is the first color of the six-color printing machine 520, is rotating at the same peripheral speed as the impression cylinder roll 55a. The roll 53a is rolled up by attaching the red ink in the ink reservoir 52a to the roll surface, and the rolled-up red ink is scraped off portions other than the engraving on the roll surface by the doctor blade 56a disposed on the side of the roll. The red ink on the surface of the plate roll 53 a is transferred to the surface of the film 100 that is wound around the impression cylinder roll 55 a and the printing of the red ink is completed on the film 100. Subsequently, after the film 100 passes through the drying zone 530 adjusted to 40 ° C. to 70 ° C. from the impression cylinder roll 55a, the film 100 passes through the adjustment rolls 514, 515, and 516, and the blue ink that is the second color of the six-color printing machine 520 is obtained. It reaches the impression cylinder roll 55b that receives the transfer. The configurations and operations of the blue ink reservoir 52b and the plate roll 53b are the same as those in the red ink portion. The subsequent four colors have the same configuration, and the film 100 is finally turned from the downward direction to the horizontal direction by the direction changing roll 517 shown on the right side of FIG. 5, and taken up by the take-up roll 518. It is done. In this way, multicolor printing is performed on the film 100 using six color inks.

  In such a multicolor printing process, it is important to adjust the position of the film 100 that travels between many rolls so that the plate rolls of the respective colors come to predetermined positions on the film 100. As shown in FIG. 6, the film 100 has a pair of marks 61 and 61 (sometimes referred to as “register marks”) at both ends or one end in the width direction at predetermined pitches.

  For example, in the red ink printing part, sensors 57a and 57a are arranged before and after the traveling film 100 passes through the impression drum roll 55a. The sensors 57a and 57a sense the positions of the marks 61 and 61 marked on the traveling film 100 at predetermined pitches and transmit the information to a controller (not shown). The controller obtains information from sensors arranged for each color, and adjust rolls 511, 512, 513; 514, so that printing of six colors is aligned on the surface of the film 100 by feedback or feedforward control. An operation command is issued to raise or lower 515, 516.

  This control mechanism is similar to that in automatic plate pressure adjustment (AGC) or automatic flatness adjustment (AFC) in metal rolling, but the resin film is inferior in rigidity as compared with the metal rolled plate. It takes time to be reflected in the system. Also, the higher the printing speed, the longer the control delay, and the more difficult it is to perform accurate control. As a result, another color print is overlaid without correcting the pitch shift. Here, “pitch shift” means that the mark 61 is displaced from the position where the mark 61 should originally be in the left-right direction on the paper surface or in the vertical direction on the paper surface in FIG. 6. The deviation in the thickness direction of the paper surface is a flutter generated between rolls, and is corrected at the roll position.However, between rolls, it causes vibrations to the system, and if there is resonance, control of printing is performed. Make it unstable.

  When a vertical / horizontal pitch shift during printing (registration shift of each plate roll) occurs, the printed matter itself becomes blurred or gradation of gradation becomes uneven, resulting in a loss of sharpness and a loss of commercial value. Further, when printing pitch shift occurs, there is a problem that the pitch shift continues in the section of several tens of meters after the occurrence, and the portion is inferior in design, so that it cannot be used as a product.

  Further, when such a defect occurs, the section must be manually removed, and the number of man-hours increases. In the above operation, since the film is joined after removing the defective portion, a seam is generated in the label roll. Since the final product with the label roll seam needs to be removed, the yield of the final product is also reduced. In addition, the seam may cause lumps in the label mounting machine, leading to problems in production of the final product.

  Furthermore, since the same final product label, bag, etc. are usually processed from a single film roll, if there is a large variation in the printability of the film wound on a single film roll, there are parts that cannot be used as products. It was a problem because it occurred in large quantities.

  Regarding the above problem, Patent Document 1 discloses a self-emulsifiable isocyanate (A) having an ethylene oxide repeating unit and two or more isocyanate groups, and at least one polymer selected from polyester, acrylic polymer and polyurethane. (B) is a coating film formed by applying a coating liquid containing at least one side of a polyester film to form a coating layer, and then drying and stretching, and a technique for defining the amount of looseness of the film is disclosed. ing. However, this technique relates to a heat-set film in which a base film is heat-set and stretched biaxially, and is a technique different from a heat-shrinkable film. Furthermore, this technique is used for base film applications such as color negatives and is not intended for high-precision printing suitability.

Patent Document 2 discloses a film having a certain degree of curvature by applying a certain tension to the film within the range of the elastic deformation limit of the film and the design / printing conditions of the printing press. However, a technique that enables printing is disclosed. However, this technique relates to a heat-shrinkable film that has been longitudinally uniaxially stretched, and is a film that has a higher tensile strength in the longitudinal direction than a heat-shrinkable film that has been laterally uniaxially stretched. This heat uniaxially stretched heat-shrinkable film has completely different printing conditions from a transversely uniaxially stretched heat-shrinkable film, so it is a technology that can solve the problems in high-precision printing of a transversely uniaxially stretched heat-shrinkable film. Absent.
JP 2004-35761 A JP 2005-292195 A

The present invention has been made in order to solve the problems of the prior art during high-speed printing, and the problem to be solved is that the fluctuation in the curvature of the heat-shrinkable film roll is suppressed, and the heat-shrinkable film roll is high in general. An object of the present invention is to provide a heat-shrinkable film roll that has good precision printability and can follow high-speed printability and sealability.
Note that “high-precision printing” refers to gravure printing using a printing plate of six or more colors and includes a portion having a gradation density of 30% or less.

  The present inventors have obtained a heat-shrinkable film roll in which printing misalignment and seal do not occur by adjusting the curvature of the heat-shrinkable film roll to a predetermined range in a film where thickness and smoothness fluctuations are observed. As a result, the present invention has been completed.

That is, the gist of the present invention is that the length is 1000 m or more , the shrinkage in the width direction after being immersed in 80 ° C. warm water for 10 seconds is at least 20%, and the shrinkage in the longitudinal direction is 8% or less. A film roll obtained by winding a certain polyester heat-shrinkable film around a core, and in the relaxation zone after heat treatment at the time of production of the film roll, the transverse relaxation rate is 0.3% or more or −0.3 %, The film temperature width at the exit of the tenter at the time of production of the film roll is within 3 ° C., and in the winder process at the time of production of the film roll, the winder tension is 30 to 100 N, and the winder tension control rate is 60 to 95. %, And in the slitting process during the production of the film roll, the slitter tension is 30 to 100 N / m, Te, flat compressive strength measured by the universal testing machine by using a paper tube is a 1800~3000N / 100mm width, the heat-shrinkable film taken at length in the longitudinal direction 5m from the film roll immediately after manufacture, The absolute value of the curvature with respect to the width direction of the center portion of the heat-shrinkable film when placed on a horizontal flat table having a long side of 5 m or more is set to 15 mm or less , the curvature measured at the core winding portion of the film roll, certain difference between the curvature was measured by unwinding unit to the polyester-based heat shrinkage film roll, characterized in that it has a 10mm or less.

  Here, “curved” means that the polyester heat-shrinkable film 11 unrolled 5 m from the longitudinal direction is placed on the horizontal surface of the rectangular bending table 10 having a long side of 5 m or more as shown in FIG. In this way, the value of the distance W (mm) deviated from the film edge and the straight line L at the center of the straight line L connecting the widthwise ends at both ends in the longitudinal direction with straight lines. As shown in FIG. 1, the curved shape of the polyester heat-shrinkable film roll includes one that curves inward with respect to the straight line L and one that curves outward. In the example of FIG. 1, the curve Wa that curves outwardly has a positive value, and the curve Wb that curves inward takes a negative value. If the values of | Wa | and | Wb | are different, the curve with the larger value is the curve of the polyester heat-shrinkable film 11.

  Further, the “polyester heat-shrinkable film collected at a length of 5 m in the longitudinal direction” may be any part of the polyester heat-shrinkable film roll (core winding part, unwinding part, or these parts). Any of the intermediate portions may be used.), Which means that any portion satisfies the above condition.

  The lower limit of the width of the polyester heat-shrinkable film is preferably 0.3 m or more, and the upper limit is not particularly limited, but is preferably 1.2 m or less from the viewpoint of handling and the like. Note that when the width of the heat-shrinkable film increases, the absolute value of the curve does not increase, but rather, the smaller the width, the easier the strain remains, and the remaining strain is less likely to relax in the width direction. The absolute value tends to increase.

Contact name when herein referred to as "A~B" (A, B is a numerical value.) Denote the above A, and is less than B.

  A polyester heat-shrinkable film roll that satisfies the provisions of the present invention can be obtained by combining a number of manufacturing process conditions from unstretched film formation to stretched film winding and slitting the wound film.

  The polyester-based heat-shrinkable film roll of the present invention is excellent in high-precision printability and can be solvent-sealed at high speed. When the width of the heat-shrinkable film roll is 0.3 m or more, if the present invention is applied, problems such as an increase in winding misalignment are less likely to occur after transporting over a long distance, so the significance of applying the present invention is great. is there.

  And since the film which has the said width | variety is excellent in workability and handling property, it is a preferable embodiment of this invention.

The polyester heat-shrinkable film roll of the present invention (hereinafter also referred to as “film roll of the present invention”) is a film roll formed by winding a polyester heat-shrinkable film having a length of 1000 m or more around a core,
(1) Absolute of curvature with respect to the width direction of the central portion of the heat-shrinkable film when the heat-shrinkable film collected from the film roll with a length of 5 m in the longitudinal direction is placed on a rectangular bending table having a long side of 5 m or more The value is 15 mm or less,
(2) The difference between the curvature measured at the core winding portion of the film roll and the curvature measured at the unwinding portion of the film roll is 10 mm or less,
(3) The shrinkage ratio in the width direction after immersing the heat-shrinkable film in warm water at 80 ° C. for 10 seconds is at least 20%,
(4) A polyester heat-shrinkable film roll having a longitudinal shrinkage of 8% or less.

  The film roll of the present invention has a subtle misalignment (registration misalignment: 0. 0) that tends to occur during high-precision printing such as multi-color high-precision printing exceeding 9 colors or gradation printing exceeding 200 m / min. (Within 3 mm).

  Below, the technical significance of how the provisions (1) and (2) above relating to the film roll of the present invention are related to the structure, function, and characteristics of the film roll will be described. In addition, the present invention provides a heat-shrinkable film roll that has good high-precision printability over all polyester-based heat-shrinkable film rolls and can follow high-speed printability and sealability. The relationship between the above two rules concerning film rolls will be clarified.

(Definition of curvature and its effect)
The film roll of the present invention is
(1) The absolute value of the curvature with respect to the width direction of the central portion of the heat-shrinkable film when the heat-shrinkable film collected at a length of 5 m in the longitudinal direction is placed on a rectangular bending table having a long side of 5 m or more is 15 mm or less. Yes, and
(2) The difference between the curvature measured at the core winding portion of the film roll and the curvature measured at the unwinding portion of the film roll needs to be 10 mm or less.

  As shown in FIG. 2, the curved shape of the film roll is, as shown in FIG. 2A, in addition to the shape in which one side is curved inward and the other side is curved outward with respect to the straight line L, as shown in FIG. One that is curved outward on both sides, one that is curved inward on both sides (FIG. 2 (B)), one that curves outward only on one side (FIG. 2 (C)), one that curves inward only on one side ( FIG. 2D) and the like. As described above, the curves W1, W2, and W5 that are curved outward take positive values, and the curves W3, W4, and W6 that curve inward take negative values.

In the film roll of the present invention, the absolute value of the curvature (in the following, when the curvature is expressed in a mathematical expression, it may be expressed as “W”) is 15 mm or less, that is, | W | ≦ 15 mm. 1)
It is. Preferably, | W | ≦ 10 mm... (2)
More preferably, | W | ≦ 5 mm... (3)
It is.
If the curvature W is within the range of the above formula (1), it is possible to suppress the occurrence of registration misalignment (deviation width: 1 mm or more) of each color that is fatal as a label during normal printing. Further, if the curvature W is within the range of the above formula (2), not only the above but also a fatal shift that tends to occur during bag making can be suppressed. Furthermore, if the curvature W is within the range of the above formula (3), it occurs not only in the above effects but also in high-precision printing such as high-precision printing exceeding 9 colors or gradation printing exceeding 200 m / min. Subtle misalignments that tend to occur can be suppressed (within 0.3 mm of misregistration).

In the film roll of the present invention, the difference between the curvature measured at the core winding portion of the film roll in one film roll and the curvature measured at the unwinding portion of the film roll (hereinafter, the difference in curvature is referred to as the difference in curvature). This is called “bending difference”, and when the bending difference is expressed in a mathematical formula, it may be expressed as “S”)) is required to be 10 mm or less. That is,
S ≦ 10mm ・ ・ ・ ・ Formula (4)
It is. Preferably,
S ≦ 8mm ... Formula (5)
More preferably, S ≦ 6 mm ··· Formula (6)
It is.
When the curvature difference S is within the range of the above formula (4), it is possible to suppress the occurrence of fatal misalignment as a label during normal printing throughout the film roll. When the curvature difference S is within the range of the above formula (5), stable printing can be performed over the entire film roll, and color unevenness called trapping can be suppressed. Further, when the curvature difference S is within the range of the above formula (6), the film travels more stably during printing, and not only the above effects but also the flutter during printing can be suppressed, so that the printing speed can be increased. it can.

(Specific method for controlling the bending W and the bending difference S)
A method for setting the curvature W and the curvature difference S of the film roll of the present invention within the above specified ranges will be described below.
1. The method controlled according to the conditions of a manufacturing process 1-1 The manufacturing process of a heat-shrinkable film roll The film roll of this invention can be obtained through three processes shown below.

(A) Extrusion process (production of unstretched film)
The unstretched film can be obtained by mixing and extruding a single resin pellet of the polyester-based resin composition or a plurality of different types of resin pellets. With respect to pellet formation and melt extrusion, it is possible to carry out by the same method as known prior art. For example, the resin composition as a raw material is melt-extruded in advance at a temperature of 200 to 300 ° C. and cut into pellets. And then the pellet-shaped resin composition can be melt-extruded at a temperature of 200 to 300 ° C.
It does not specifically limit as an extrusion method, A T-die method, a tubular method, etc. can be used. As an example, the left side of FIG. 3 illustrates a film manufacturing apparatus in which an extruder 31, a T die 32, and a casting roll 33 are arranged in this order. In the case of the T-die method, after extrusion, the film can be rapidly cooled on a casting roll having a surface temperature of 15 to 80 ° C. to form an unstretched film having a thickness of 30 to 300 μm.

(B) Longitudinal stretching step (production of a longitudinally stretched film)
Thereafter, the unstretched film is longitudinally stretched with a difference in peripheral speed of the roll while applying heat with a temperature control roll or an infrared heater (range indicated by A in FIG. 3). Using a longitudinal stretching roll, an unstretched film is subjected to a roll temperature of 60 to 120 ° C., preferably 60 to 80 ° C., and a stretching ratio of 1.0 to 1.3 times, preferably 1.0 to 1.1 times. A stretched longitudinally stretched film is obtained.
In this specification, “longitudinal direction” is the same as the longitudinal direction of the film roll, “lateral direction” is synonymous with the width direction of the film roll, and “longitudinal stretching” is the longitudinal direction of the film roll (of the heat-shrinkable film). Stretching in the flow direction) and “lateral stretching” mean stretching in the width direction of the film roll (perpendicular to the flow direction of the heat-shrinkable film).

(C) Transverse stretching step and winder step A laterally stretched film can be obtained by stretching the film obtained in the longitudinal stretching step using a tenter stretching method with a tenter device 34 (see FIG. 3). After the above-mentioned longitudinally stretched film is stretched transversely under the conditions of a stretching temperature of 55 to 100 ° C., preferably 70 to 90 ° C., a draw ratio of 1.7 to 7.0 times, preferably 4.0 to 7.0 times, It heat-processes at the temperature of 60-120 degreeC, Preferably it is 70-110 degreeC, and it winds up as the master roll 35, obtaining the press of the touch roll 36, applying tension with the winder apparatus 37.

(D) Slit process Then, as shown in FIG. 4, the master roll 35 is unwound and applied to the slitter 40, and is slit to an arbitrary width. In the example of FIG. 4, the film divided into three is wound up in a length direction of 1000 m or more and 20000 m or less, preferably 1000 m or more and 10000 m or less, more preferably 1000 m or more and 8000 m or less, and the film rolls 41 to 43 of the present invention. It becomes. In this case as well, when the film is wound, the film rolls 41 to 43 that are being tensioned are pressed by the touch rolls 44 to 46 (hereinafter referred to as “contact pressure”).

  Of the above processes, the influence of the curvature W and the curvature difference S of the film roll is mainly the stretching process and the winder process (because the influence of the curvature is the situation at the time of film-forming winding). . Hereinafter, a method for controlling the horizontal winding width of the film roll and the post-tilt winding width in these two steps will be described.

1-2 Control of the bending W and bending difference S of the film roll in the stretching process In order to suppress the winding shift of the winding core part, it is effective to suppress the bending and loosening of the film, and the optimum relaxation rate It is desirable to have. In general, when a plastic film is wound in a roll shape while stress and strain biased in the width direction remain, immediately after winding or at the stage of unwinding and used, the remaining stress and strain are relaxed over time, It is considered that the entire film roll is distorted and curved.

  In order to eliminate such distortion, it is necessary to devise so as not to apply a thermal history biased in the width direction of the film roll. As such a device, for example, the convergence difference (draw) between rolls applied in the longitudinal stretching process is adjusted to an optimum value, or the distortion in the film after heat treatment is released, so that the relaxation rate is optimized. Means for changing the width of the tenter rail or making the tenter hot air flow uniform in the width direction so that the width direction of the film roll has a uniform temperature are effective.

  In addition, the speed ratio (between the preheating roll / low speed roll or between the high speed roll / cooling roll) between the rolls in the longitudinal stretching (that is, when no longitudinal stretching is applied) having a longitudinal stretching ratio of 1 is intended to remove slack. It is preferable to adjust in the range of 0.980 to 1.020. By making this speed ratio 0.980 or more, although it does not participate in bending, it is possible to suppress the occurrence of wrinkling of the film and meandering of the film running. Moreover, by making this speed ratio 1.020 or less, along with the stretching orientation in the longitudinal direction, the distortion generated at each roll cycle can be suppressed, and the width fluctuation of the film and the promotion of bending can be suppressed.

In addition, each tenter zone for transverse stretching is relaxed and cooled after preheating, stretching and heat treatment, but if relaxation is not performed, distortion of the heat treatment remains and the curvature tends to increase. Therefore, when the bending state is in the middle slack state as shown in FIGS. 2B and 2D, in the relaxation zone, −0.3 to −5.0% relaxation (that is, the lateral direction). To 0.3 to 5.0%), the distortion in the lateral direction of the film, especially at the ends near the tenter clip, is readjusted in the tenter, and the film is evenly re-constrained to generate curvature. Can be suppressed. On the other hand, as shown in FIGS. 2 (A) and 2 (C), when the bending state is outward slack, the film is laterally relaxed by 0.3 to 5.0% in the lateral direction in the relaxation zone. The distortion of the direction, especially near the tenter clip, can be released in the tenter, the film restraint can be evenly released and curving can be suppressed.

  When the lateral relaxation rate is -0.3 to 0.3%, distortion during heat treatment remains and the curvature tends to increase. Therefore, in the present invention, in the relaxation zone after the heat treatment, by adjusting the lateral relaxation rate to 0.3% or more or −0.3% or less, the residual stress is released, and the bending caused by the bowing phenomenon is caused. It is preferable to suppress. Further, it is preferable to adjust the rate of relaxation in the lateral direction to 5.0% or less, or −5.0% or more, because it is possible to suppress the looseness of the film at the exit of the tenter and realize uniform winding.

  In order to suppress fluctuations in the film thickness, it is desirable to keep the temperature variation in the width direction constant in each tenter zone, and the hot air blowing speed in each tenter zone of preheating / stretching / heat treatment / relaxation / cooling is 10 m / second. Preferably, the difference in hot air velocity in the width direction is preferably within ± 3 m / second. When the hot air blowing speed and the hot air speed difference are adjusted as described above, the film temperature range measured with a non-contact thermometer can be within 3 ° C. The film end of measurement is measured in the width direction from a position 50 mm away from the clip end. This is because if it is within 50 mm, the film temperature cannot be accurately measured due to the influence of the clip radiant heat.

1-3 Control of film roll bend W and bend difference S in winder process After the tenter exit, both ends of the ear are slit and removed, and the web is wound with a winder. The winder tension is 30 to 100 N / m. It is preferable. When the value of the curve closer to the tenter clip is a large positive (+) value, the curve can be reduced by increasing the tension. Conversely, when the curvature closer to the tenter clip is a large negative (−) value, the curvature can be reduced by lowering the tension. However, when the tension is increased, winding tightening is likely to occur. In that case, it is necessary to take a method of relaxing winding tightening by oscillation or a method of adjusting the diameter and amount of fine particles to make it difficult to tighten. It is.

  The winder contact pressure is preferably 5 to 70 N / m so as not to cause winding deviation.

  Furthermore, the tension and the contact pressure from the winding start to the winding end are not constant, and the curvature can be suppressed by changing according to the winding diameter. As a specific example of suppressing the bending, a method of decreasing the tension and increasing the contact pressure as the winding diameter increases is preferable. The tension at the end of winding is 60 to 95% of the tension at the start of winding, and the contact pressure is The curvature value of the master roll can be controlled by adjusting the winding end value with respect to the starting value to 100 to 300%. In the winder, the winding deviation can be suppressed by attaching a flange to the end face of the film when winding.

  More specifically describing the film winding process in the winder, the winder tension and the winder contact pressure are proportionally constant from the start of winding to the end of winding so that the final winding state = winding start state × control rate. Adjusted to change. For example, when the winder tension is 100 N / m and the tension control rate is 50%, a tension of 100 N / m is applied at the beginning of winding, the tension is gradually decreased in proportion to the length, and tension is applied at the end of winding. Is 50 N / m.

1-4 Control of Film Roll Curve W and Curve Difference S in the Slit Process The tension applied to the film in the slitter directly affects the film roll curve W and curve difference S. In order to set the curvature W and the curvature difference S of the film roll within the range defined by the present invention, the slitter tension of the film roll after slitting and removing both ends of the master roll should be 30 to 100 N / m. preferable. By adjusting the tension in the slitter within the above range, it is possible to suppress the bending of the master roll in the slit process.

2. Method of controlling by physical properties of film By imparting appropriate surface slipperiness to the film constituting the film roll, a film roll satisfying the curvature W and the curvature difference S defined by the present invention can be obtained, and other physical properties can be obtained. Can also be secured. Specifically, the method of apply | coating or adding a filler and an antistatic agent to the resin composition which comprises a film can be mentioned.

2-1 Addition of filler The resin composition constituting the film contains inorganic and / or organic fine particles (filler) from the viewpoint that when it is made into a heat-shrinkable film, blocking resistance and slipperiness can be imparted. It is preferable.
In the blocking process, when the film roll is unwound in the printing process, the film unwound from the roll adheres to the outermost layer film on the roll side, generates abnormal noise, and causes fluctuations and fluctuations in tension, resulting in unstable printing. This is not preferable. When slipperiness is given to the film, when winding and unwinding the film on the roll, the positional freedom increases between the film and the roll body, enabling smooth winding and unwinding. Become.
The content of the fine particles is preferably in the range of 0.005 to 1% by mass, more preferably in the range of 0.01 to 0.7% by mass, particularly 0.02 to 0.5% by mass with respect to the entire film. % Is preferable.

  If the fine particle content is 0.005% by mass or more, slipperiness is appropriately imparted, and the occurrence of extreme blocking can be suppressed. If it is 0.01% by mass or more, slipperiness is imparted, and a thick stretched portion caused by longitudinal stretching rolls and non-uniform uniformity in the width direction of the tenter temperature is blocked between the films. Winding pressure is applied as it approaches the winding core, and it is possible to suppress the occurrence of slack and increased bending. If it is 0.02% by mass or more, the slipperiness is further imparted, and the portions with a slight vertical thickness fluctuation generated periodically from the equipment such as the extruder and the cooling cast roll are blocked between the films. Winding pressure is applied as it approaches the winding core, and it is possible to suppress the occurrence of slack and increased bending.

  On the other hand, if the fine particle content is 1% by mass or less, extreme unevenness on the entire film surface can be suppressed, ink loss can be suppressed, and the occurrence frequency of winding deviation can be reduced. If it is 0.7 mass% or less, the dispersibility of microparticles | fine-particles will rise and it can suppress partial ink omission. If it is 0.5 mass% or less, the unevenness | corrugation of the whole film surface can be controlled, and the ink omission of the shallow dot of a printing plate can be suppressed.

  Specific examples of the inorganic fine particles include silica, alumina, titania, kaolin, clay, calcium carbonate, calcium phosphate, lithium fluoride, carbon black, and alkali metal, alkaline earth metal, phosphorus at the time of polyester polymerization. Examples of precipitates resulting from a catalyst such as a compound, and organic fine particles include various cross-linked polymers.

  The average particle diameter of these fine particles is preferably in the range of 0.1 to 6.0 μm, more preferably in the range of 0.5 to 5.0 μm, particularly 1.0 to 0.5 from the viewpoint of the effects described above. It is preferably in the range of 4.0 μm. Here, the average particle diameter means a 50% volume average particle diameter (d50) measured by a method such as an electromagnetic wave scattering method such as a laser diffraction method or a dynamic light scattering method, or a light transmission method such as a centrifugal sedimentation method. To do. If there is a difference depending on the measurement method, the value obtained by the laser diffraction method is used.

  If the average particle diameter of the fine particles is 1 μm or more, slipperiness is moderately imparted and blocking can be suppressed. If it is 0.5 μm or more, slipperiness is imparted, and the thick portion where the vertical thickness fluctuation caused by the longitudinal stretching roll and the tenter temperature is not completely uniform is blocked between the films, and the roll core Winding pressure is applied as it approaches the portion, slack is generated, and bending can be prevented from increasing. If the thickness is 1.0 μm or more, slipperiness is further imparted, and a portion with a slight vertical thickness fluctuation generated periodically from equipment such as an extruder and a cooling cast roll is blocked between the films, and the roll core It is possible to suppress the slack that occurs when pressure is applied as it approaches the part. If it is 6.0 micrometers or less, the extreme unevenness | corrugation of the whole film surface can be suppressed, ink omission can be suppressed, and the generation | occurrence | production frequency of winding deviation can be reduced. If it is 5.0 micrometers or less, the dispersibility of microparticles | fine-particles will rise and it can suppress partial ink omission. If it is 4.0 micrometers or less, the unevenness | corrugation of the whole film surface can be controlled, and the ink omission of the shallow dot of a printing plate can be suppressed.

  The method for mixing the fine particles is not particularly limited, and the fine particles can be added during the polymerization process of the resin, and can also be mixed during the production process of the resin composition or the molding process of the heat-shrinkable film. Moreover, when it becomes easy to enter wrinkles as it approaches the roll core, the generation of wrinkles can be suppressed by blending in the direction of increasing the diameter of the fine particles or increasing the amount.

2-2 Application of antistatic agent An antistatic agent can be applied to the film roll of the present invention. For example, the coating roll speed is applied to the film after longitudinal stretching before lateral stretching with a tenter while the antistatic agent is swirled with a roll that is 0.1 to 1.5 times the line speed. An antistatic effect can be imparted to the film.

  The coating type antistatic agent is mainly a surfactant, and there are various types of antistatic agents such as cationic / anionic / mixed ion based on the type of surfactant. A mixed ion system is often used.

  Next, the resin composition of the film which comprises the film roll of this invention is demonstrated. In the present invention, the resin composition of the film is a polyester resin, which will be described in detail below.

<Resin composition of heat-shrinkable polyester film roll>
The polyester resin constituting the film roll of the present invention is preferably a polyester resin having terephthalic acid as a dicarboxylic acid component and ethylene glycol, that is, an ethylene terephthalate unit as a main constituent unit as a polyhydric alcohol component.

  Furthermore, ethylene glycol is used to form an ethylene terephthalate unit in 100 mol% of the polyhydric alcohol component. Others, triethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,4-butanediol, 1,6-hexanediol, 3-methyl-1,5-pentane Diol, neopentyl glycol, 2-methyl-1,5-pentanediol, 2,2-diethyl-1,3-propanediol, alkylene glycol such as 1,9-nonanediol, 1,10-decanediol, Alicyclic diols such as 1-cyclohexanedimethanol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,2-cyclohexanediol, 1,4-cyclohexanediol, Trimethylolpropane, glycerin, pentaerythritol, di Ji glycol, dimer diol, polyoxytetramethylene glycol, polyethylene glycol, bisphenol compounds or alkylene oxide adducts of derivatives thereof are possible combination like.

  When the alicyclic diol component is obtained by reacting a dicarboxylic acid compound and a diol compound to obtain a polyester resin, a part of the alicyclic diol compound is mixed in the diol compound to form a single copolymer. It can be included. In addition, a polyester resin obtained by reacting a dicarboxylic acid compound and an alicyclic diol compound is synthesized and mixed with a polyester resin obtained by reacting a dicarboxylic acid compound and a diol compound such as ethylene glycol other than the alicyclic diol compound. It can also be made to contain.

  In 100 mol% of the polyvalent carboxylic acid component, terephthalic acid is used to form an ethylene terephthalate unit. In addition, aromatic dicarboxylic acids, ester-forming derivatives thereof, and aliphatic dicarboxylic acids can be used in combination. Examples of the aromatic dicarboxylic acid include isophthalic acid, naphthalene-1,4- or 2,6-dicarboxylic acid, 5-sodium sulfoisophthalic acid, 1,4-cyclohexanedicarboxylic acid, orthophthalic acid, phenylenedioxydiacetic acid, 4 , 4′-diphenyldicarboxylic acid, 4,4′-diphenoxyethanedicarboxylic acid, 4,4′-diphenyletherdicarboxylic acid, 4,4′-diphenylsulfonedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6- And naphthalenedicarboxylic acid or its ester-forming derivatives. Examples of the aliphatic dicarboxylic acid include glutaric acid, adipic acid, sebacic acid, azelaic acid, oxalic acid, succinic acid, dimer acid, malonic acid or ester-forming derivatives thereof.

  When the aromatic dicarboxylic acid component is reacted with a dicarboxylic acid compound and a diol compound to obtain a polyester resin, a part of the aromatic dicarboxylic acid compound is mixed in the dicarboxylic acid compound to form a single copolymer. Can be included. In addition, a polyester resin obtained by reacting an aromatic dicarboxylic acid compound and a diol compound is synthesized and mixed with a polyester resin obtained by reacting a diol compound and a dicarboxylic acid compound such as terephthalic acid other than the aromatic dicarboxylic acid compound. It can also be made to contain.

  The polyester resin according to the present invention can be produced by a batch method or a continuous method by a conventional method for producing a polyester resin, that is, a direct polymerization method or a transesterification method. Here, the optional copolymerization component can be added at any stage of the polycondensation reaction process. Alternatively, an oligomer having a low polymerization degree can be produced from a dicarboxylic acid compound and a diol compound, and a polyester resin can be produced by polycondensation of the oligomer with an arbitrary copolymer component.

  The resin obtained by the polycondensation reaction is usually extracted in the form of a strand from an extraction port provided at the bottom of the polycondensation reaction tank, and is cooled with water or after water cooling, and then cut into a pellet by cutting with a cutter. Furthermore, by subjecting the pellets after polycondensation to heat treatment and solid phase polycondensation, the degree of polymerization can be further increased, and reaction by-products such as acetaldehyde and low-molecular oligomers can be reduced.

  In the above production method, the esterification reaction is performed in the presence of an esterification reaction catalyst such as antimony trioxide, an organic acid salt such as antimony, titanium, magnesium, calcium, or an organic metal compound, if necessary. The transesterification reaction is performed in the presence of a transesterification reaction catalyst such as an organic acid salt or an organic metal compound such as lithium, sodium, potassium, magnesium, calcium, manganese, titanium, or zinc, if necessary.

  The polycondensation reaction is performed in the presence of phosphorus compounds such as orthophosphoric acid, phosphorous acid, hypophosphorous acid, polyphosphoric acid, and esters and organic acid salts thereof, and, for example, antimony trioxide, germanium dioxide, The reaction is performed in the presence of a metal oxide such as germanium tetroxide or a polycondensation catalyst such as an organic acid salt or an organic metal compound such as antimony, germanium, zinc, titanium, or cobalt. Of these polycondensation catalysts, at least one selected from tetrabutoxy titanate, antimony trioxide, and germanium dioxide is preferably used. Further, an antifoaming agent such as silicone oil can be added to promote defoaming in the polycondensation process.

  In the polyester resin according to the present invention, the intrinsic viscosity measured at 30 ° C. in a mixed solvent of phenol / 1,1,2,2-tetrachloroethane (mass ratio 1: 1) is usually 0.4 to 1.5 dl. / G is preferable. When the intrinsic viscosity is 0.4 dl / g or more, sufficient mechanical properties can be obtained, and when it is 1.5 dl / g or less, molding is easy. From these viewpoints, the intrinsic viscosity under the above conditions is more preferably in the range of 0.6 to 1.2 dl / g.

  The resin composition according to the present invention may be mixed with other resins as long as the effects of the present invention are not impaired. For example, polyethylene, polypropylene, these modified maleic anhydrides, polyolefin resins such as ionomers, thermoplastic resins such as polyamide resins and polystyrene resins, thermoplastic elastomers, and the like.

  Further, the resin composition is an antioxidant such as phenol, phosphorus or thioether, a light stabilizer such as benzotriazole, benzophenone, benzoate, hindered amine or cyanoacrylate, an inorganic or organic crystal. Additives such as nucleating agents, molecular weight modifiers, hydrolysis resistance, antistatic agents, lubricants, mold release agents, plasticizers, flame retardants, flame retardant aids, foaming agents, colorants, dispersion aids, and glass fibers Further, reinforcing materials such as carbon fiber, mica and potassium titanate fiber may be contained.

<Layer structure of film>
The film constituting the film roll of the present invention is not limited to a single layer, and can be a multilayer film in which other layers made of different materials or homogeneous materials are laminated. The multilayer film can be composed of a plurality of layers according to applications such as 2 types, 2 layers, 2 types, 3 layers, 3 types, 5 layers, 4 types, 7 layers.

<Size of film roll>
The film roll of the present invention is a polyester-based heat-shrinkable film wound while applying an arbitrary tension to the core, preferably having a width of 0.3 m or more and an effective length of 1000 m or more. The upper limit of the length of the film is not particularly limited, but from the viewpoint of handling and the like, it is desirably 20000 m or less, preferably 10,000 m or less, and more preferably 8000 m or less. The upper limit of the width of the film roll is not particularly limited, but is preferably 1.2 m or less from the viewpoint of handling and the like. It is preferable that it is 1.0 m or less. Even if the width increases, the absolute value of the curve does not increase. Rather, the smaller the slit width, the easier the strain remains, and the residual stress is less likely to relax in the width direction, so the absolute value of the curve tends to increase. There is.

<Core>
The core used for the film roll of the present invention is not particularly limited, and a paper tube, a metal tube, a plastic tube, or the like can be used. Among these, paper tubes are the most versatile from the viewpoint of ease of handling and cost, and are preferable from the viewpoint of easy availability. Furthermore, there is a processing advantage that the film roll can be slit together with the core. When a paper tube is used as the core, it is preferable that the flat pressure resistance measured by the universal material testing machine for the paper tube is 1800 to 3000 N / 100 mm width. By setting the flat pressure resistance of the paper tube to 1800 N / 100 mm width or more, the core is hardly deformed even if there is a slight tightening, and winding deviation due to the core deformation can be prevented. Further, by setting the flat pressure resistance of the paper tube to 3000 N / 100 mm width or less, it is possible to suppress the standing of the winding start portion. Various methods can be considered for adjusting the core strength, but it is effective to increase the strength by coating a thermoplastic resin such as polyurethane resin.

<Heat shrinkability>
The polyester heat-shrinkable film constituting the film roll of the present invention has a shrinkage ratio in the width direction of at least 20%, preferably 30% or more, more preferably 40% or more when immersed in warm water at 80 ° C. for 10 seconds. There must be. Moreover, it is preferable that the thickness of a heat-shrinkable film is the range of 10-100 micrometers. When the shrinkage rate of the heat-shrinkable film is 20% or more, it can be used as a general packaging application. Further, when the shrinkage rate is 30% or more, it can be used as a shoulder label of a general heat-resistant PET bottle. Furthermore, if the shrinkage rate is 40% or more, the temperature range during shrinkage can be lowered, so that it can be used as a shoulder label for non-heat-resistant PET bottles. Moreover, when thickness is 10 micrometers or more, there exists an advantage that secondary processing is easy, and the film exceeding 100 micrometers tends to be inferior to workability. In addition, although the heating method at the time of carrying out the heat shrink of the label produced with the film roll of this invention mainly includes the heating by steam, it can be shrunk by a heating method such as hot air or infrared rays. .

   The heat-shrinkable film constituting the film roll of the present invention has a film roll shrinkage of 8% or less, preferably 6% or less, more preferably 4% or less when immersed in warm water at 80 ° C. for 10 seconds. It is desirable that

  If this shrinkage rate is 8% or less, the top plate of the packaged item will be used when it is used for the purpose of packaging with the top plate and the bottom of the packaged item (for example, packaging of cups, etc.) And the film can be prevented from coming off from the bottom. Moreover, if this shrinkage rate is 6% or less, it can be used for the wound label (for example, PET bottle) which is not packaged with a top plate and a bottom. Furthermore, if this shrinkage rate is 4% or less, there is little longitudinal shrinkage, so that the label length can be reduced when used as a body-wound label, which can contribute to yield improvement.

<Application of film>
The covering for covering the label produced by the film roll of the present invention needs to withstand the heat at the time of filling the contents and to withstand the heat at the time of the heat shrinkage. Examples include glass bottles and steel cans, polyethylene and polypropylene cups and trays, and polyester bottles. Examples of the contents include food such as lunch boxes, oil, milk, juice, beer, cosmetics, pharmaceuticals, stationery, and the like.

  EXAMPLES The present invention will be specifically described with reference to examples, but the present invention is not limited to these examples. The resin raw materials, film resin compositions, evaluation methods, evaluation results, etc. used in the examples and comparative examples are described in detail below.

<< Analysis of resin raw materials >>
About the 8 types of resin raw materials mentioned later, the composition analysis, intrinsic viscosity, and the measurement of ash content were performed with the following method.

(Composition analysis of polyester resin)
A polyester resin solution sample was analyzed by monitoring ¹ H with a nuclear magnetic resonance apparatus (NMR), and the dicarboxylic acid component was mol% based on the total dicarboxylic acid component, and the diol component was mol% based on the total diol component. Asked.

(Measurement of intrinsic viscosity (dl / g))
About 0.25 g of polyester resin is dissolved at about 110 ° C. in about 25 ml of a mixed solvent of phenol / tetrachloroethane (mass ratio 1/1) at 110 ° C. and then cooled to 30 ° C. The intrinsic viscosity was measured at 30 ° C. with a solution viscometer (“2CH type DJ504” manufactured by Chuo Rika).

(Measurement of ash content)
About 10 g of the sample was fired in a muffle at 700 ° C., and the mass before and after firing was measured to calculate the content of the particulate matter.

<< Resin raw material >>
The following eight polyester resins (PET1 to 8) were used as pellet raw materials for the resins used in the film production of the film rolls of the examples and comparative examples.

(1) Polyester resin 1 (PET1)
“EASTAR PETG Copolyester 6763” manufactured by Eastman Chemical Co. was used. As a result of composition analysis of the polyester resin by the above-described method, the dicarboxylic acid component was terephthalic acid (hereinafter abbreviated as “TPA”), and the diol component was abbreviated as ethylene glycol (hereinafter abbreviated as “EG”). The polyester resin was 68 mol% with respect to the total diol and 1,4-cyclohexanedimethanol (hereinafter abbreviated as “CHDM”) was 32 mol% with respect to the total diol. Moreover, it was 0.78 dl / g as a result of measuring the intrinsic viscosity of this polyester resin by the said method.

(2) Polyester resin 2 (PET2)
A polyester resin was produced by the method of Production Example 1 described below. As a result of the composition analysis of the polyester resin by the above-described method, the dicarboxylic acid component was such that TPA was 70 mol% with respect to the total dicarboxylic acid, and isophthalic acid (hereinafter abbreviated as “IPA”) was the total dicarboxylic acid. It was 30 mol% with respect to the polyester resin whose diol component was EG. Moreover, it was 0.72 dl / g as a result of measuring the intrinsic viscosity of this polyester resin by the said method.
-Production Example 1-
Using a batch polymerization apparatus equipped with a slurry preparation tank, an esterification reaction tank, a polycondensation tank, and a pelletizing apparatus, put a mixture of TPA and IPA (molar ratio 4: 1) and 1 ton of EG esterification reaction product. In the esterification reactor, TPA prepared in the slurry preparation tank: 605 kg (3.64 kg), IPA: 259 kg (1.56 kg) and EG: 388 kg (5.20 kg) (dicarboxylic acid and diol Esterification reaction was carried out by continuously adding a slurry having a molar ratio of 1: 1.2) at a rate of 314 kg / hr. In the esterification reaction, 200 mass ppm of antimony trioxide is added to the theoretical yield of the polyester resin as the esterification reaction catalyst under the conditions of a reaction temperature of 250 ° C. and atmospheric pressure, and the produced water is continuously distilled. However, the esterification reaction was carried out until the reaction rate reached 95%. After completion of the esterification reaction, 1 ton of the esterification reaction product was left in the esterification reaction vessel, and the esterification reaction product was transferred to the polycondensation vessel.
Subsequently, orthophosphoric acid was added as a stabilizer to the polycondensation tank to which the esterification reaction product had been transferred, and cobalt acetate and diantimony trioxide were added as polymerization catalysts (both were added as an EG solution). The addition amounts of orthophosphoric acid, cobalt acetate, and antimony trioxide were 60 mass ppm, 150 mass ppm, and 200 mass ppm, respectively, with respect to the theoretical yield of the polyester resin.
Thereafter, the pressure is reduced from normal pressure to 1.33 × 10 ² Pa (1 mmHg) over about 100 minutes, the internal temperature is increased from about 250 ° C. to about 280 ° C., and the melt polycondensation reaction is performed while distilling EG. went. After 4 hours from the start of decompression, the pressure was restored and the polycondensation reaction was completed. After returning the pressure in the polycondensation tank, the polyester resin was drawn out into water in the form of a strand from the bottom of the tank, and then cut into pellets.

(3) Polyester resin 3 (PET3)
“NOVADURAN 5008” manufactured by Mitsubishi Engineering Plastics was used as the polyester resin 3. As a result of analyzing the composition of the polyester resin 3 by the above method, it was a polyester resin in which the dicarboxylic acid component was TPA and the diol component was 1,4-butanediol (hereinafter abbreviated as “BD”). . Moreover, it was 0.85 dl / g as a result of measuring the intrinsic viscosity of the polyester-type resin 3 by the said method.

(4) Polyester resin 4 (PET4)
A polyester resin was produced by the method of Production Example 2 described below. As a result of performing ash analysis and composition analysis by the above-mentioned method for the polyester resin, the dicarboxylic acid component is TPA, and the diol component is EG 68% by mole based on the total diol, and CHDM is based on the total diol. As a result of ash content analysis, it was a polyester resin containing 10% by mass of inorganic fine particles that are not organic. Moreover, it was 0.76 dl / g as a result of measuring the intrinsic viscosity of this polyester resin by the said method.
-Production Example 2-
90 parts by mass of the polyester-based resin PET1 and 10 parts by mass of “Silysia 320P” having an average particle size of 2.7 μm manufactured by Fuji Silysia Chemical Co., Ltd. were extruded with the same direction twin screw extruder, and then the polyester resin was fed from the die part. The strand was extracted into water and then cut into a pellet.

(5) Polyester resin 5 (PET5)
A polyester resin was produced by the method of Production Example 3 described below. As a result of performing ash analysis and composition analysis by the above-mentioned method for the polyester resin, the dicarboxylic acid component is TPA, and the diol component is EG 68% by mole based on the total diol, and CHDM is based on the total diol. As a result of ash content analysis, it was a polyester resin containing 10% by mass of inorganic fine particles that are not organic. Moreover, it was 0.74 dl / g as a result of measuring the intrinsic viscosity of this polyester resin by the said method.
-Production Example 3-
90 parts by mass of the polyester-based resin PET1 and 10 parts by mass of “Silysia 420” having an average particle size of 3.1 μm manufactured by Fuji Silysia Chemical Co., Ltd. are extruded with a twin-screw extruder in the same direction. The strand was extracted into water and then cut into a pellet.

(6) Polyester resin 6 (PET6)
A polyester resin was produced by the method of Production Example 4 described below. As a result of performing ash analysis and composition analysis by the above-mentioned method for the polyester resin, the dicarboxylic acid component is TPA, and the diol component is EG 68% by mole based on the total diol, and CHDM is based on the total diol. As a result of ash content analysis, it was a polyester resin containing 10% by mass of inorganic fine particles that are not organic. Moreover, it was 0.70 dl / g as a result of measuring the intrinsic viscosity of this polyester resin by the said method.
-Production Example 4-
90 parts by mass of the polyester-based resin PET1 and 10 parts by mass of “Silysia 430” having an average particle size of 4.1 μm manufactured by Fuji Silysia Chemical Co., Ltd. are extruded by the same-direction twin screw extruder, and then the polyester resin is fed from the die part. The strand was extracted into water and then cut into a pellet.

(7) Polyester resin 7 (PET7)
Esterification reaction of a mixture of TPA, EG and neopentyl glycol (hereinafter referred to as “NPG”) using a batch polymerization apparatus equipped with a slurry preparation tank, an esterification reaction tank, a polycondensation tank, and a pelletizing apparatus. Esterification reaction was carried out by continuously adding slurry of TPA: 820 kg, NPG: 128 kg and EG: 291 kg prepared in a slurry preparation tank at a rate of 314 kg / hr to an esterification reaction tank containing 1 ton of product. went. In the esterification reaction, 200 mass ppm of antimony trioxide is added to the theoretical yield of the polyester resin as the esterification reaction catalyst under the conditions of a reaction temperature of 250 ° C. and atmospheric pressure, and the produced water is continuously distilled. However, the esterification reaction was carried out until the reaction rate reached 95%. After completion of the esterification reaction, 1 ton of the esterification reaction product was left in the esterification reaction vessel, and the esterification reaction product was transferred to the polycondensation vessel.
Subsequently, orthophosphoric acid was added as a stabilizer to the polycondensation tank to which the esterification reaction product had been transferred, and cobalt acetate and diantimony trioxide were added as polymerization catalysts (both were added as an EG solution). The addition amounts of orthophosphoric acid, cobalt acetate, and antimony trioxide were 60 mass ppm, 150 mass ppm, and 200 mass ppm, respectively, with respect to the theoretical yield of the polyester resin.
Thereafter, the pressure is reduced from normal pressure to 1.33 × 10 ² Pa (1 mmHg) over about 100 minutes, the internal temperature is increased from about 250 ° C. to about 280 ° C., and a melt polycondensation reaction is performed while distilling EG. It was. After 4 hours from the start of decompression, the pressure was restored and the polycondensation reaction was completed. After returning the pressure in the polycondensation tank, the polyester resin was drawn out into water in the form of a strand from the bottom of the tank, and then cut into pellets. Moreover, it was 0.70 dl / g as a result of measuring the intrinsic viscosity of a polyester-type resin by the said method.

(8) Polyester resin 8 (PET8)
“RT-523C” manufactured by Nippon Unipet Co., Ltd. was used. As a result of composition analysis of the polyester resin by the above-described method, the dicarboxylic acid component was terephthalic acid, and the diol component was 98 mol% of ethylene glycol with respect to the total diol, diethylene glycol (hereinafter abbreviated as “DEG”). ) Was a polyester resin of 2 mol% based on the total diol. Moreover, it was 0.70 dl / g as a result of measuring the intrinsic viscosity of this polyester resin by the said method.

<< Production of Film Roll >>
The film roll of the following Examples 1-12 and Comparative Examples 1-5 was obtained using the above 8 types of resin raw materials. Table 1 shows a list of blending and Table 2 shows a list of film production conditions.

Example 1
55 parts by mass of the raw material polyester resin PET1, 27 parts by mass of the polyester resin PET2, 15 parts by mass of the polyester resin PET3, and 3 parts by mass of the polyester resin PET4 are blended, and a vacuum vent is drawn by a 270 ° C. same-direction twin screw extruder. The mixture was melt kneaded while being extruded from a T die die onto a cooling roll to obtain an unstretched film having a thickness of 250 μm. Thereafter, the film was subjected to longitudinal stretching between a low-speed roll and a high-speed roll of a longitudinal stretching machine at a magnification of 1.1, and the draw ratio between the rolls was 1.01. Thereafter, preheating at 103 ° C. in a tenter, stretching at a stretching temperature of 80 ° C. and a stretching speed of 3000% / min in the transverse direction perpendicular to the casting extrusion direction, and processing at a heat treatment temperature of 92 ° C. A heat-shrinkable film having a tenter relaxation rate of 0.7% and a thickness of 50 μm was obtained. Regarding the blowing of tenter hot air, the average speed was 12 m / sec, the speed difference in the film width direction was 2 m / sec, and the temperature width in the film width direction at the tenter outlet was 1 ° C. Moreover, the tension for winding the film with a winder is 70 N / m, the contact pressure of the rubber roll for guiding the film is 30 N / m, the final value at the end of winding relative to the initial value at the start of winding is 85% for tension and contact pressure, respectively. Adjusted to 200%. Furthermore, the tension for winding the film with a slitter is 70 N / m, the contact pressure of the metal roll for guiding the film is 170 N / m, the final value at the end of winding relative to the initial value at the start of winding is 50% for tension and contact pressure, respectively. The film roll according to Example 1 was obtained by adjusting to 200% and slitting to a width of 0.98 m and winding up by 1000 m.

(Examples 2 to 12; Comparative Examples 1 to 5)
The resin blended according to the blending table of Table 1 was melt extruded under the same conditions as in Example 1 to obtain a 250 μm film. In addition, the unit in a table | surface is a mass part.
The film was stretched, wound and slit under the conditions shown in Table 2 to obtain a film roll. The conditions other than those in Table 2 were all drawn, wound and slit in the same manner as in Example 1.

In addition, the film roll manufacturing conditions of the said Examples 1-12 and Comparative Examples 1-5 were measured in the following ways.
(Film temperature measurement)
The film temperature at the exit of the tenter was measured with a non-contact infrared thermometer “THI-440N” manufactured by TASCO. The measurement positions were 5 points between the film center / both ends / left. If both ends are within 50 mm from the tenter clip, the film is affected by the radiant heat of the clip, and an accurate film temperature cannot be measured.
(Tenter relaxation rate)
The relaxation rate during the heat treatment was recorded.
(Hot air blowing speed)
The measurement was made using an anemometer at the hot air outlet of the tenter nozzle.
The measurement positions were 5 points between the center of the tenter nozzle / both ends / left, and the average of 5 points was defined as the “hot air blowing speed”.
(Hot air velocity difference in the width direction)
The difference between the maximum speed and the minimum speed at each of the five measurement positions in the width direction was defined as “the difference in hot air speed in the width direction”.
(Film temperature range)
The difference between the maximum temperature and the minimum temperature at each measurement position at five points in the width direction was defined as “film temperature width”.

<< Film Roll Evaluation Method >>
Below, the evaluation method of a film roll is demonstrated. The evaluation results are summarized in Table 3.
(1) Curvature and Curvature Difference As shown in FIG. 1, a film that has been unwound by 5 m in the longitudinal direction from the unwinding portion and the core winding portion of the film roll is placed on a rectangular bending table 10 that is a horizontal plane. Each of the values | Wa | and | Wb | shifted from the film edge and the straight line L at the center of the straight line L that is left to stand so as not to be loosened and connects the end portions in the width direction at the widthwise ends with straight lines. (Mm) was measured, and the value with the larger absolute value was recorded as “curvature”. Also, the measurement value defined below was recorded as “bending difference”.
(Curved difference): A core “winding portion” is a sample of a film taken from the end portion on the winding start side of the film that has been wound around one film roll to the outside of 5 m. Similarly, the “unwinding portion” is a sample of the film taken from the end on the winding end side of the film to the place wound inside 5 m. The difference between the curvature value measured at the core winding portion of the film roll and the curvature value measured at the unwinding portion of the film roll is defined as “curvature difference”.
Note that “curvature” refers to an actually measured distance with ± with respect to the 0 reference, and “curvature value” refers to a numerical value obtained by converting the “curvature” into an absolute value.

(2) Shrinkage at 80 ° C. The film obtained in each example or comparative example was cut to a size of 150 mm in the measurement stretching direction and 25 mm in a direction perpendicular to the measurement stretching direction to prepare a sample. Marks at intervals of 100 mm are attached to the extending direction of the sample, immersed in a warm water bath at 80 ° C. for 10 seconds, and then immersed in cold water at 23 ° C. for 30 seconds, and the marked line interval (A (mm)) is measured. The shrinkage rate was calculated by the following formula (7).
Shrinkage rate (%) = 100 × (100−A) / 100... Formula (7)

(3) Printing evaluation After storing film rolls in a cold storage warehouse maintained at 20 ° C. for half a year, a non-antistatic surface is used at a speed of 150 m / min using a color chart plate generally used with a 6-color printing machine. 6-color printing was performed. The registration deviation accuracy of the registration deviation monitoring device was observed, and the average of the registration deviations over the entire roll was taken as the value of the registration deviation.
○: Register displacement is less than 0.3 mm △: 0.3-0.9 mm
X: The registration shift exceeds 0.9 mm.
When the misregistration is less than 0.3 mm, the blur is not felt visually. When the misregistration is 0.3 to 0.9 mm, it is slightly blurred, but there is no problem as a product. When the misregistration exceeds 0.9 mm, the blur is bad and the commercial value is lost.

(4) Core pressure strength FIG. 7 shows an outline of the test. The paper tube was cut into 100 mm in the width direction, and stored for 24 hours in an atmosphere at a temperature of 23 ° C. and a humidity of 50%. The sample 70 was set in the hydraulic servo “UH-10A” manufactured by Shimadzu Corporation, and the maximum strength when the sample was compressed at a compression speed of 10 mm / min was measured and recorded as “core pressure strength”.

  As is clear from Table 3, the absolute value of the curvature of the film roll is 15 mm or less, and the difference between the curvature measured at the core winding portion of the film roll and the curvature measured at the unwinding portion of the film roll is 10 mm or less. It is clear that the film roll is excellent in practicality after aging at room temperature for half a year. The film roll of the present invention can perform high-precision printing over the entire film roll as a heat-shrinkable film roll for high-precision printing, which is now increasing, and can improve the printing yield.

It is a figure which shows the principle of a measurement of curvature roughly. It is a figure which shows roughly the modification of the curvature which arises in a film roll. It is the schematic which shows the manufacturing process of a master roll. It is a figure which shows a slit process schematically. It is a figure which shows a multicolor printing process roughly. It is a figure which shows the state which the sensor has detected the mark described on the film. It is a figure which shows the pressure strength test of a paper tube.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Film roll 2 Surface plate 3 Horizontal surface 10 Curved base 11 Sample film 31 Extruder 32 T die 33 Casting roll 34 Tenter device 35 Master roll 36 Touch roll 37 Winder device 40 Slitter 41, 42, 43 Film roll 44, 45, 46 Touch Roll 51 Unwinding roll 52a, 52b Ink reservoir 53a, 53b Plate roll 55a, 55b Impression drum roll 56a, 56b Doctor blade 57a, 57b Sensor 61 Mark 70 Paper tube 100 Film 510, 517 Direction conversion roll 511-516 Adjustment roll 518 Winding Roll 520 Gravure printing machine
530 Drying zone

Claims (3)

A polyester heat-shrinkable film having a length of 1000 m or more , a widthwise shrinkage of at least 20% after being immersed in warm water at 80 ° C. for 10 seconds, and a longitudinal shrinkage of 8% or less A film roll wound around a core,
In the relaxation zone after the heat treatment in the production of the film roll, the lateral relaxation rate is 0.3% or more or -0.3% or less,
The film temperature width at the exit of the tenter during production of the film roll is within 3 ° C,
In the winder process during production of the film roll,
Winder tension is 30-100N,
Winder tension control rate is 60-95%,
In the slitting process when manufacturing the film roll,
The slitter tension is 30-100 N / m,
By using a paper tube whose flat pressure resistance measured by a universal material testing machine is 1800 to 3000 N / 100 mm width as the core,
Curvature with respect to the width direction of the central portion of the heat-shrinkable film when the heat-shrinkable film collected from the film roll immediately after production at a length of 5 m in the longitudinal direction is placed on a horizontal flat table having a long side of 5 m or more. of the absolute value and 15mm or less, the curvature and measured by the core winding portion of the film roll, polyester, characterized in that not more than 10mm the difference between the curvature was measured by the unwinding of the film roll Netsuchijimi Film roll. The polyester heat-shrinkable film roll according to claim 1, wherein a winder contact pressure is set to 5 to 70 N / m and a winder contact pressure control rate is set to 100 to 300% in a winder process during production of the film roll. A polyester heat-shrinkable film having a length of 1000 m or more, a widthwise shrinkage of at least 20% after being immersed in warm water at 80 ° C. for 10 seconds, and a longitudinal shrinkage of 8% or less A method for producing a film roll wound around a core,
In the relaxation zone after the heat treatment in the production of the film roll, the lateral relaxation rate is 0.3% or more or -0.3% or less,
The film temperature width at the exit of the tenter during production of the film roll is within 3 ° C,
In the winder process during production of the film roll,
Winder tension is 30-100N,
Winder tension control rate is 60-95%,
In the slitting process when manufacturing the film roll,
The slitter tension is 30-100 N / m,
As the core, using a paper tube whose flat pressure resistance measured by a universal material testing machine is 1800 to 3000 N / 100 mm width,
Curvature with respect to the width direction of the central portion of the heat-shrinkable film when the heat-shrinkable film collected from the film roll immediately after production at a length of 5 m in the longitudinal direction is placed on a horizontal flat table having a long side of 5 m or more. The polyester thermal shrinkage is characterized in that the absolute value of is not more than 15 mm, and the difference between the curvature measured at the core winding portion of the film roll and the curvature measured at the unwinding portion of the film roll is not more than 10 mm. Method for producing a conductive film roll.

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